Customers are warned of bogus firms pretending to be authorised to take the data as well as hackers obtaining information from the Financial Conduct Authority could cause the most problems

“We cannot refuse to hand over data because that’s what the legislation says, but we will have to try to educate people to understand the vulnerability.”

David Crawford, head of current accounts at NatWest, believes the launch of the scheme could cause confusion for customers – and hackers will take advantage.

He said: “With all the new companies expected to launch propositions, customers might not be aware of which are genuine and which are run by criminals, and so be at risk of giving away details or even money.”

It comes after millions of people had their smartphones infected by a new form of malware which secretly drains their bank account.